Syrian president Bashar al-Assad, facing three months of protests against his rule, today promised that a "national dialogue" would start soon.

In his first speech in two months, Dr Assad also said he would ask the Justice Ministry to study expanding a recent amnesty, but said it was important to differentiate between "saboteurs" and people with legitimate demands.

He blamed the ongoing unrest in the country on a foreign conspiracy and accused the opposition of using the protests to cause sectarian divide.

"The conspiracy was designed abroad and perpetrated within our country," he said. The protests were marked by "vandalism, murder and the destruction of private property," he added.

His speech in Damascus comes as his forces sweep through the northwestern border region with Turkey blocking refugees fleeing a military crackdown on protests against his autocratic rule.

The operation along the border follows the biggest protests in four months of anti-Assad unrest on Friday which a violent clampdown has failed to quash. Security forces shot dead up to 19 protesters on Friday, rights groups said.

Dr Assad will address "current circumstances", the state news agency said, his first speech since April 16th and only his third since protests began in the southern Hauran Plain on March 18th.

Syria's ambassador to Washington said in a newspaper interview his government differentiates between the legitimate demands of protesters and those of armed gangs and said Dr Assad will deal with "all these issues in his speech".

More than 10,000 Syrian refugees have already crossed into Turkey and Turkish officials say another 10,000 are sheltering close to the border just inside Syria in the olive groves and rich farmland around the town of Jisr al-Shughour.

But Syrian human rights campaigner Ammar al-Qurabi said the army was now stopping those still inside Syria from leaving.

"The Syrian army has spread around the border area to prevent frightened residents from fleeing across the border to Turkey," he told Reuters. Mr Qurabi also accused pro-government forces of attacking people trying to aid the refugees as they fled.

The violence so close to its border challenges Turkey's foreign policy of "zero problems with neighbours" that has seen it befriend the Middle East's autocratic rulers while presenting itself as a champion of democracy.

Turkish Prime Minister Recep Tayyip Erdogan Turkey has pledged to keep his borders open to refugees and has called the Syrian government crackdown "savagery", but beyond words, it is not clear whether Ankara's rapprochement with Damascus has earned Turkey any influence with Assad to halt the violence.

Syrian troops and gunmen loyal to Dr Assad seized the town of Bdama, only 2 km from Turkey on Saturday